IEM - In Ear Monitoring

Hi all,

Thought it might be interesting to hear about other peoples experience, suggestions, recommendations on the subject of IEM's.

I guess we're all aware of the benefits of IEM, they can protect your hearing from damage from high level sounds, and they can feed you with exactly the mix you want and or need to hear while performing. It can also fix the problem of the Doppler effect (this is where reflected sound can reach the ears of the vocalist slightly off pitch and cause them to sing perfectly slightly off pitch and of course no wedge monitors to carry around and or cause feedback issues.

I had been using Shure SE 425's but in spite of them being supplied with an assortment of interchangeable buds I've found it impossible so far to get an ideal reliable fit.

The 'perfect fit' to my way of thinking is, they feel comfortable and stay in place and they have an ideal bleed, or vent so that the ear canal doesn't totally seal air-tight as this causes the Occlusion effect (when the ear canal is sealed from the outside sound reverberates between the seal and the ear drum).

Given the limited success using the Shure devices I decided to invest almost £600 in having professional custom IEM's made. Fair to say the sound quality is fantastic, they fit perfectly, easy to install, easy to remove and easy to forget they are even there after just a few minutes... provided you don't move around or make any vocal sound! The problem is the Occlusion effect still persists as they do not have vents.

Discussing this issue with the tech department of the manufacturer they say quite rightly that venting the IEM's will degrade the overall sound quality, it will leak sound out and they will exclude less external noise. Personally I'd be happy to trade some sound quality and leakage if it dispenses with or at least significantly reduces the Occlusion effect.

Seeing and listening to top-class professional performers who use IEM's I cannot imagine they would put up with unwanted reverberating low frequency sound in their ears. Neither can I imagine they could tolerate singing and dancing with each dance step sounding like rolling thunder in their head!

Has anyone out there got any experience or suggestions to solve the problem... maybe I just went to the wrong 'experts' of IEM's for vocalist fold-back use?

Any thoughts anyone?

I use IEM's occasionally. I agree, the isolation is a challenge. Whats worked for me is placing a mic somewhere to pick up ambient noise (the crowd, band members talkin, ext). You can bleed in as much ambient noise from the mic as you like into your IEM.  Keep that mic isolated to just your aux out for your ears. No One else will even know its there 🙂 

Yes, forgot to mention that particular tip. I use an inexpensive omnidirectional condenser microphone to hear the audience... best thing about that is... you can turn it off! (needs smiley emoticon).


I was using IEM's and specifically the Shure's like you.  Part of my going with the BOSE units a few years ago was to get rid of the isolation of IEM's from the audience by placing the BOSE units back-line to enhance audience interaction.  Works great for small rooms and intimate settings.  To be honest, we've settled on the smaller format and enjoy it to the point where I think it is extending my music career.  The smaller arrangement fits in the back of the pick-up, no trailer to haul, and my back feels great the next day after a gig.  Good luck in your quest to find a better arrangement that suits your format.  


Hi Wes,

Actually I went with Bose for the same reason of eliminating the need for additional fold-back/monitoring. However, I still prefer IEM because it does isolate you from things you don't want to hear and it doesn't matter where I am in a venue, it all sounds the same to me. Doesn't matter if I'm in front or behind the speakers. I use Shure wireless microphone and wireless IEM so I can wander around if I wish... I can perform in one pub and at the same time have drink in the pub next door if I like Haha! 


Cool beans on the wireless stuff.  Reminds me of my larger rig where I run a headset wireless and guitar wireless on the same guitar strap.  These days we're running a 4-piece live group with 2 Model II's w/ B-2 bottoms and T1's.  The BOSE is a bit under-powered for the volumes that group likes to run.  With the track-backed duo, one unit does great and the patrons love the lower SPL's, especially folks with hearing aids.  Those buggers distort so easily that we make believers out of patrons who think they can no longer enjoy live music.  When they are there, we relent of the 80's hairband stuff toward more of the Steely Dan, Boz Skaggs, & Tom Jones vintage material.  😉  Nothing like relating to your audience.  Keep 'em rocking in Leominster!!!




Hey Wes,

You noted that you are running a 4 piece with 2 L1 M2 wit B2's and that its underpowered. I am looking to do the same, except concerned if they have enough "juice" for it. What have you found to be the issues?

Hi rtz, in my experience you can get a lot of music power out of two L1M2 B2's and we've never needed to run them at maximum or anywhere near.   We are a 4-piece rock band and like to play at a reasonable (to us) volume. We have found the real issue to be feedback from mics as you up the overall volume level, especially if you are using the back-of-stage position for the Bose columns - which is most definitely my preferred arrangement.  If all attempts to defeat the feedback fail (eg. filtering, re-positioning things, etc) but you still want to make more noise, then my preference is to augment the forward sound with a couple of powered PA speaker units at the front of the stage, driven from the L1's or from your mixer.  These can be adjusted independently of the L1's to raise the volume level into the audience without messing up the on-stage balance or contributing to the feedback.  The downside is having to carry a bit more gear around, but only for larger venues.

Alternatively you could put the L1's to the front and have wedge monitors on the stage, but in my view the main benefit to the band of having the L1's is then lost.


We've had good success in the back-line config, I think because we are strict in using only the T1's as the input with applicable input presets from the factory.  Any other mixer/sub-mixer arrangement led to feedback issues.  We also run direct vocal input to the units cross stage from each other to increase headroom.  Never a hint of feedback here.



My four-piece (two guitars, one bass, one percussionist, all whom sing) routinely puts the L1 off to the left of group j-u-s-t ahead of the line of our three mics (our percussionist is behind us with a vocal mic and a condenser or two over his kit). The three of us up front still get plenty of sound IN MOST SITUATIONS without any need for monitors. We do run an auxiliary Soundcraft board into Channel 3 (vocals) and Channel 4 (instruments), and I use Ch. 1 for my vocals & Ch. 2 for my guitar (I have it set this way so I can do solo gigs without any messing around). We run a line out of the T1 to a S1 that the percussionist routinely uses as his monitor of the FOH mix. In those rare occasions where the three of us need a monitor up front, I daisy chain from the percussionist's S1 to another S1 to the right of our bassist/vocalist on the right side of the stage and blow the FOH mix back across the three of us. 

We have played a ton of places and this setup can be hauled in by the four of us in one trip and we can be ready to go in just under an hour (i.e., PA, lights, tuned up). Plus, at the end of the gig we can still hear with no ringing ears! We have been doing this for a couple of years and have no complaints! 

Good Luck,


I don't often play in high volume situations where the side wash from Bose systems isn't enough to monitor well but have been trying out a couple of IEM solutions.

The cheap Shures that came with the wireless rig were hopeless.  I got a pair of Etymotic in ears and they're somewhat better but as you've said, isolating.

I was thinking of trying a pair of Westone Am Pro 20s - quick in and out and they allow some ambient sound in as well (thus the "Am") but I spent the money on a new '61 SG Standard with Maestro Vibrato instead.  😉

PS: The next time I play at one of the fancy hotels up the coast, I'm going to bring my own splitter, mixer and in-ear monitor and tell them to turn the **** wedges OFF!  The last time was a terrible experience with distorted sound from the monitors that seriously degraged our performance.

All good points above guys - thanks.  I guess we all go about things in slightly different ways to get the same result.  Our band is also a 4-piece - 2 elec guitars, bass and electronic drums - with four SM58 mic's for the vocals, all fed into the mixer and then into the L1M2's.  We always use the L1's in the back-of-stage position (left and right) and don't normally have any problems with feedback that can't be managed.  The mixer has a very good EQ section which enables us to cope pretty well with different room acoustics.  We have occasionally played with the L1's just ahead of the mic line and although that has worked reasonably well for us, we much prefer the L1's to be behind us.  That way we can hear everything, can maintain a good balance and we know exactly what the audience is hearing.  The back-of-stage arrangement of the two L1's just gives a feeling of being immersed in the overall sound, and you don't seem to get that with a FOH PA system and foldback monitors.

We would only use additional FOH speakers if necessary to augment the overall sound volume, whilst still keeping the L1's at the back. 



Mean while on the IEM front... I've learned a bit more and read some Doctors and engineers explanations, the biggest problem is the occlusions. Apparently the ear canal starting from the outside is cartilage covered with skin but as you go deeper in it becomes bone covered in skin, and its reported that its the cartilage area that causes the occlusions. If the IEM canal tube is long enough to reach the bone area, apparently the occlusions either do not exist or are at least not perceived. However, at that depth its dangerously close to the eardrum!

There is in fact a report on Trust Pilot of a guy who says his eardrum was damaged by the audiologist who took the impressions! Perforated eardrum, a lot of pain and deafness and months of recovery, so it says.

An alternative to going in deep to reduce the occlusions is to allow the plug to breath. However, reducing the seal has dramatic effects on loss of frequency response starting at the low end.

There are some companies who manufacture IEM's with what they call "Ambient Filters", meaning they are vented through a filter to let ambient sound in (so you can hear the audience etc.). The vent kills the occlusion and the "head under water" feeling, great, what about frequency performance? Well, it seems they either specify or at least imply that the frequency response remains fantastic, which suggest they have found a way to alter the rules of physics.

If you've never used IEM's you can get a feel for it if you put a finger in each ear, gently but enough that it feels sealed. Now hum something like E2 (different pitches for different people) and you should hear that in your head probably quite loud, if its not loud then adjust the note up or down a bit. When you've got that, slowly press your fingers tighter into your ear canal, you should find that the harder you press so the sound becomes quieter and more natural.

My custom IEM's are now back with the manufacturer being re-molded with longer canal tubes... lets hope they don't poke my eardrums out! I dare say we'll find out in a week or two.

A brother-in-law of mine (now deceased) always used to say, "Never put anything smaller than your elbow in your ear-hole"... that could be the best advice on this subject. 


Just yesterday I received my re-worked custom IEM's back from ACS the manufacturer... WOW! The difference is absolutely incredible! So far as I know all they did was extend the canal tubes. Occlusions? What occlusions? The sound quality I'm getting is so good its totally bonkers! The feeling of "I've got my head stuck in a tin bucket full of water" has totally evaporated.

So now I've had to spend more cash to upgrade my radio gear, so I've bought a Shure P3T transmitter with the P3R receiver. I'll report back on that when I've tried it out 

Hi Dave Hazel.

Have you seen The L1® Approach and the History of Amplification?

I haven't had to think about monitors (in ear or other) since I got my first L1.


Hello ST,

With respect I would doubt there is much you could tell me about the history of amplification/sound reinforcement that's of any consequence in the real world, equally I am also aware of the Bose approach. It's a good approach, it's a very practical approach and a very tidy approach, and I would also argue that it is probably the best cost effective method too. But the simple fact is Bose do not have all of the solutions to all of the potential issues that performers may need to overcome. As such, the Bose back of stage PA method absolutely cannot provide a solution to my particular requirements.

By day I'm just a time-served development engineer in the field of dedicated microprocessor controlled wireless alarm/monitoring systems that help to keep people alive in hospitals/care homes etc. I haven't worked in professional audio for something like 35 years or more. When it comes to music, essentially I'm just a serious hobbyist come part-time semi-professional, which means sometimes I accept a fee and sometimes I don't. But that doesn't mean that I hold anything back when it comes to presenting myself as a performing vocalist, I give it the best as I can in terms of the overall quality of the audio output and presentation.

By virtue of Shure wireless systems I am totally untethered by either cable or visual lyric prompt. In fact I do have a lyric prompt system that is totally invisible. All power to anyone who can accurately remember all the lyrics to a couple of hundred songs at any point in time but the fact is, I personally cannot rely on myself to be able to do so. 

I'm well aware that many people use such things as tablets, laptops, smartphones etc. that are able to operate as a prompting system. In fact, that is exactly how I used to do it when I first ventured into this hobby. But, it is not ideal, equally my system would not be idea for everyone but it is for me.

Given that the Bose PA systems in question are it would seem 'supposed' to be the ultimate solution for performers, considering how popular the visible synchronised prompting method is, its a real shame that Bose do not include a decent display/media player within the compact T mixers!

ST, I trust that answers your question as to weather or not I need a history lesson on sound reinforcement methods or Bose sales methodology? I do not have any issues in respect of where I am in relation to the PA, except that more gain before feedback is available if the mic is off axis. But that is NOT why I use an IEM system 

Getting back to my IEM system and the actual purpose of this thread.... based on my experience so far I would say there is little point in messing about with the budget priced equipment. Get some good quality off-the-shelf wired IEM's to test if its the way you want to go or not. If you decide it is, then get yourself custom molded IEM's and a quality wireless system.

The sound quality of the ACS IEM's (now they have sorted them out) is so good I cannot overemphasise the fact. Because I can now hear everything in higher definition than the L1 can deliver, its made things more comfortable, which in turn has improved my performance and confidence. At the same time it doesn't matter where I am in relation the the PA stack.

Shure claim that the P3T-P3R is so clean and solid you wouldn't know you're on wireless and not hard-wired. Because of the fantastic definition of the ACS IEM's it seems there is a very slight, and I mean VERY slight softening of definition compared to hard-wire but its of no concern whatsoever. I would guess that one of the reasons its so clean and noiseless is because its digital which may raise questions in respect of digital latency. It cannot be zero latency but whatever it is, its nothing that I've be able to notice.

I ventured into the IEM world several years ago investing in a Sennheiser wireless system with custom ear units.
I could never manage to get a satisfactory mix and gave up on them in the end (an expensive venture). I work mostly solo and the biggest problem I had was getting the house mix to sound the same as the mix in my ear monitors. I prefer to hear the full mix even on the rare occaisions I have to use floor monitors which allows me to hear what my audience is hearing and always have a good sound.
Your posts here have enthused me to maybe try once again with some new in ears. 90% of the time I am very happy with the Bose system behind or to the side and rarely in front with additional foldback or side fill monitors for me. The only time I have issues with monitoring is with restaurant gigs when house levels have to be so low sometimes it is difficult for me to hear the backing or even myself, this makes it very uncomfortable for me and I am sure affects my performance, I like to feel the music. I believe with the right system, IEM's can solve this for me providing I can overcome the issue of matching the mixes.

Hi Eric'sson,

I have had the low volume issue too, not in a restaurant as such but I occasionally go and do a turn at a local care home in an open lounge where the overall sound level needs to be what the audience wants, which may not be the same as what I want or need.

As for getting the right mix, I would setup the PA with 'naked' ear-holes then apply the IEM and simply use that as the reference as my IEM is a clone of Pre-Master output. I hear exactly the same as the audience only with better definition on account of the IEM delivering higher definition than the L1 can produce.

I'm using 100% backing tracks, no live instruments, so my levels are fixed at a known source level. My voice level is controlled naturally relative to the level of the backing track. So it is no different to using the PA as the monitor, except it is in fact much better and easier to control on the basis that it doesn't matter where I am in relation to the position of the PA stack(s) or whatever the PA level needs to be, it just doesn't matter to me if its relatively low level, typical level, or they want it LOUD... its all the same to me.

It's a fact that it wasn't easy to deploy an IEM system with the T1 mixer, and I was on the brink of buying an "ART MyMonitor" to make things easier to manage. But then I spotted the T4s, being a 4/2 i was able to reduce my equipment device count and tidy things up.

I think the people at ART have rationalised matters the same as I have. Solo performers only need a small compact mixer. However, it seems that the designers behind compact mixers seem to think that AUX sends/returns, pan-pots and monitor mixes etc. are not required! The ART MyMonitor provides a solution to the problem, or the typical short fall of compact mixers.

I had bought budget equipment to start with, fact is, I needed to prove the system before I invested too much cash. The system works perfectly for me, so it was just a matter of improving and upgrading the equipment. Admittedly is wasn't cheap with the cost of the T4s, the Shure P3/T/R and the custom IEM's but I would say that my set is now about as perfect as its ever going to get, it is pretty much self-contained and VERY portable and the overall sound quality is top class for the audience and myself 


I hear what you are saying but my experience differs from yours. I also use the full house mix for my IEM's but it doesn't reproduce the same hence the problem, what I am hearing in my IEM's isn't the same as what I hear from the speakers when I take them out. Even though it's the same mix from the mixer the backing tends to sound a lot louder in the IEM's and I found myself adjusting the mix accordingly only to find that when I listen to the house the backing isn't loud enough so there is a balance problem that needs resolving. I need to spend some time to achieve a monitor mix that compensates and matches the house mix and I have not had the time to do that ..... one day.